This invention relates to a combined ventilator and light unit, and more particularly to a safety device for preventing the overheating of a ventilator/light unit of the type that is particularly suited for residential bathroom use.
A combination ventilator/light unit of the type described normally incorporates an electric fan for exhausting air from a bathroom, or the like, and a lamp which is operable independently of the fan. Underwriters Laboratories, Inc., Standard 507 (electric fans), which sets the industry guidelines for bathroom ceiling ventilator safety devices, has for years permitted such incorporation of a light compartment in a bathroom ventilator. With the current awareness of a need for conserving energy, however, many new homes are now heavily insulated, particularly in the ceiling areas. Because of this increased insulation, there appears to be a substantially greater danger of undesirable heat build-up in units of the type described.
In order to improve the operational safety of residential bathroom ventilator/light combinations of the type described, it is clear that some means must be provided for accurately sensing and avoiding excessive heat build-up in units of the type described.
It is an object of this invention, therefore, to provide for combined ventilator/light units of the type described a system or device for sensing and preventing undesirable heat build-up in such units.
It is further object of this invention to provide for combined ventilator/light units of the type described a novel heat sensing and control circuit which includes a pair of heat sensors, at least one of which makes use of the ventilator portion of the unit automatically to prevent any undesirable heat build-up in the unit.
Still another object of this invention is to provide a novel safety device of the type described which is mounted on the ventilator/lamp housing in such manner that it is substantially tamper proof when being installed.
Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawings.